Collapsible container



Feb. 23, 1965 R. E. PIERSON COLLAPSIBLE CONTAINER Filed Dec. 4, 1962 United States Patent 3,170,600 COLLAPSHBLE CONTAINER Robert E.'Pierson, East Greenwich, R.I., assignor to United States Rubber Company, New York, N.Y., a corporation of New Jersey Filed Dec. 4, 1962, Ser. No. 242,177 1 Claim. ;(Cl. 222-94) When the container is empty, this central part collapses into a doubly covered rectangle.

' Containers constructed according to the disclosure of the aforementioned patent are admirably suited for the storage of gas and liquids, as well as for their transportation. However, such a container has not heretofore been adapted to the storage of pulverulent materials, such as dry powdered cement, mortar, flour or powdered plastic, because of the difficulty of emptying the materials therefrom. Accordingly, this invention concerns an improvement to the above-mentioned Cunningham container, and my principal object is 'to improve such a container so that it will be well suited to the storage and transportation of pulverulent material and will facilitate the emptying of such material in an expeditious manner.

This fundamental object is accomplished by providing the container with a bladderlayer having an air-permeable fabric center section which is adapted to aerate pulverulent material in contact therewith so that such material can be easily emptied from the container.

The bladder layer comprises a rectangular sheet of coated' cord fabric attached about its periphery to the lower wall of the container, thusto form'a chamber therewith. The air-permeable fabric center section is itself attached about its periphery to the lower wall of the container, thereby to form a second chamber.

There are means to fill the container. The container has an opening in the upper wall thereof for introducing gas under pressure into the container. 0nd opening through both the lowerwall of the container and the center section of the bladder layer for emptying the container. wall of the container for introducing. gas under pressure into the first chamber formed by the rectangular sheet of coated cord fabric, thus to force pulverulent material in contact with the bladder layer onto the center section thereof. A fourth opening is provided through the lower wall of the container for introducing gas under pressure into the chamber formed underneath the center section, thereby to aerate pulverulent material on the center section and assist the same out of the emptying opening.

For a better understanding of these and other characteristics and advantages of the present invention, ref-v erence should be had 'to'the following description of the accompanying drawings relating to an embodiment thereof, wherein,

FIG. 1 is a cross-sectional view taken longitudinally through a container of the type disclosed in the aforementioned Patent No. 2,930,423; I

FIG. 2 is a partial view taken along line 2-2 of-FIG. l and showing the air-permeable fabric center section of the bladder (layer; s

. FIG. 3 is a transversecross-sectional view through the A third opening is-provided in the lower There is a seccontainer of FIG. 1 taken on line 33 thereof, the pha torn line portion showing the bladder layer in the inflat position; and 7 FIG. 4 is a cross-sectional view taken on line 44 FIG. 2.

Referring to the drawings, there is shown a collapsil container 10 of the type disclosed in Patent No. 2,930,42 Container 10 is formed of a number of layers 11 of re tively flexible fabric material, as, for example, coat cord fabric, in the manner disclosed in the patent. [Cc tainer 10 has a substantailly cylindrical body porti 12, which by the nature of its construction is 'compris of a lower Wall 13 and an upper wall 14. I

As shown in the drawings, container 10 is provid with a bladder layer 15, which is preferably formed rubberized cord fabric and is generally of the same si asthe lower wall 13 of the container.

Positioned in the center of bladder layer 15 is an a permeable fabric strip 16, formingthe. center secti thereof. The fabric of strip 16 preferably takes the for of any low permeability woven fabric material and c be made of cotton or other suitable fibers. The pt meabil'ity of the fabric should be such that under low pressures, e.g., approximately one-half to five pounds 1: square inch, it is possible to pass from two to twel cubic feet of air per minute through each square foot area.

Bladder layer 15 is attached about 'its'periphery the inner surface of lower wall 13 of the container an airtight manner. This is accomplished by using lllbbt fabric hinges 17, as shown in FIGS. 3 and 4.

Fabric strip 16 is also attached about its periphe to lower wall 13 of the container in an airtight mannt This is also accomplished by the use of rubber-fab: hinges 2t) and 21, as shown in FIGS 3 and 4. .St cifically, air-permeable fabric strip 16 itself is attach about its periphery .to the rubberized cord fabric'of bla der layer 15 by rubber-fabric hinges 20; and the rubbr izedcord fabric of bladder layer 15 is attached to low wall 13 of the container by hinges 21.

By this construction there is formed an airtight char her I, which extends circumferentially around the lovt wall 13 of the container, being bounded by the rubberiz cord fabric of bladder layer 15 on the top, lower w.

13-01? the container on the bottom, and by rubber-fab: hinges 17 and 21 on the sides. The method ofattac ment also forms a second chamber II, as shown in PIC 3 and 4. Chamber II is impermeable on its hottc surface, being bounded there by lower wall 13 of t containenbutis airrpermeable on its .upper surface, sin the same is formed by fabric strip 16.

The collapsible container thus equipped is provid with a number of openings and fittings therein for pro; operation. There is a filling fitting 1?, which may positioned on the upper wall 14 of the container. The is also a general pressurizing air inlet 22a inserted in opening 22 in the upper wall 14-of the container. Air other gas under pressure is introduced into the contair through opening 22 to make the container rigid pri to the emptying operation.

A second opening 23 is positioned in the lower w 13 of the container. A fitting 23a is provided in ope ing 23 and extends through both the outer wall and t air-permeable fabric'strip 16. Fitting 23:: provides t means of egress for the lading and alternatively, m also serve as the filling means in the absence of fitting 1 A third opening 25 is also provided in lower w 13 of the container and includes an air, inlet 25a. 1 or other gas under pressure introduced into chamber of container 10 through opening 25 inflates bladder 1213 15 in the manner indicated by the phantom lines in F1 As chamber I isextended outwardly, pulverulent erial in contact with-the rubberized cord fabric of lder layer 15 is pushed onto the air-permeable fabric 16. inally, a fourth opening 27 is provided in lower wall of the container spaced from the other openings ein and is equippedwith a suitable air linet 27a. Air )ther gas under pressure is introduced through open- 27 into chamber II underneath fabric strip 16, thus erate and fluidize the lading in contact therewith. It uld be understood that opening 27 extends only through er wall 13 of the container, and, although it isposied beneath fabric strip 16, as is opening 23 (see FIG. it does not extend through fabric strip 16 as does hing 23. i 1 operation container is emptied of a lading of erulent material as follows: he container is first inflated with air or other gas er pressure though opening 22 in upper wall 14 there- 3 a pressure approximating oneahalf to one pound per are inch. This makes container 10 rigid. Fitting is then opened, thus to provide a means of egress the lading.

tir or other gas under pressure is then introduced ugh inlet 27a into chamber 11 in an amount sufnt to pass approximately two to twelve cubic feet vtir per minute per square foot through fabric strip As the air passes through fabric strip 16, it aerates fluidizes pulverulent material in contact therewith. the lading exits through fitting 23a, additional air or :r gas under pressure is forced into chamber I through t 25a, thus to cause bladder layer to be extended he manner shown by the phantom lines in FIG. 3. .s extended, bladder layer 15 urges the lading inwardoward fabric strip 16. As this additional material )rced onto the air-permeable fabric strip, it is aerated :he air or other gas passing therethrough, thus causthe material to flow readily through fitting 23a and of the container. .n opening 28 may also be provided at the end of container, as shown in FIG. 1, to serve as an alternate ms of emptying the container. When the container laced on a sloping surface and aerated as above de- Jed, it may be preferable to use opening 28 as the us of egress for the lading, rather than opening 23. Ihile the invention has been shown and described as :parately-prepared bladder layer in a container, it 11d be readily understood that the additional layer .d also be made as an integral part of lower wall 13. s, if lower wall 13 of the container were to consist of or more plies of rubberized cord fabric as is coniional, a parting material, e.g., paper, talc, etc., could placed during lay-up between those rubberized cord 3 which would ultimately serve as lower wall 13 of the :ainer and the ply which would serve as bladd vl 4 15. The air-permeable fabric strip 16 could then be properly positioned parallel to the longitudinal axis of the cylindrical body portion of the container, and would be 7 attached to the lower wall 13 thereof in the manner shown in FIG. 4, i.e., by the use of rubber-fabric hinges 20 and 21. In this manner. container 10 could be equipped with the bladder layer of the instant invention, and yet would be of no heavier construction thanordinary containers, inasmuch as the bladder layer 15 would also constitute part of the load-bearing lower wall when deflated.

Having thus, described my invention, what I claim and declare to protect by Letters Patent is:

A collapsible container adapted for the storage of pulverulent material, said container being formed of relatively flexible material, comprising:

a substantially cylindrical body portion having upper and lower walls closed at their ends to form a con tainer;

means to fill said container;

a bladder layer comprising a rectangular sheet of coated cord fabric attached aboutits periphery to said lower wall of said container thereby to form a first chamber, 7

said sheet being generally coterminous withsaid lower Wall of said container, said sheet having an air-permeable fabric center section disposed parallel to the axis of said cylindrical body portion,

said center section being attached about its periphery to said lower wall of said container thereby to form a second chamber;

a first opening in said upper wall of said container for introducing gas under pressure into said container;

a second opening through said lower, wall of said container and said center section of said bladder layer for emptying said container; I

a third opening through said lower wall ofsaid c011 tainerspaced from said second opening for introducing gas under pressure into said first chamber to force pulverulent material in contact vwith said bladder layer, onto said center section thereof;: and a fourth opening through said lower wall of said container spaced from said second and thirdopenings for introducing gas under pressure into said second chamber to aerate pulverulent material on said center section. I

References Cited in the file of this patent UNITED STATES PATENTS 2,930,423 Cunningham Mar. 29, 1960 FOREIGN. PATENTS 624,286 Canada July 25, 1961 

